Friday, November 30, 2007

Knife hinges (2)...

I mentioned in the previous post how careful to be when mortising the hinge recesses with hand tools. A good approach is to use a sharp marking knife and sharp chisels of different sizes. I make sure to mark the outline of the straight knife hinge carefully using the marking knife, this creates a tiny notched line which allows me to set the tip of my chisels into. Accuracy is greatly increased using this technique over using a pencil line. The mortise recess itself is created in stages, being careful not to remove too much wood in each pass. Once a substantial depth of the recess has been created, I find the mortising goes along much quicker as there is less opportunity for the chisel blade to skate across the edge of the board. The chisel is tapped in lightly into the marked line, creating sufficient depth to remove each layer of wood from the mortise recess.

Initially, I had placed the door on the already mounted hinge leaves in the carcase, confirmed my measurements and simultaneously made a secondary mark or notch of where to orient the door hinge on the edge of the door. After creating the initial depth of the hinge mortise, I test fit the door to the already installed hinges on the carcase by sliding it in and confirming my markings are correct. You can see I spend a considerable amount of time confirming all measurements and markings are correct since it is not a simple task to correct any of this afterwards as the hinge mortises are already created. This is probably a good place to have practised these steps on some spare boards to get it right.

In the photo above, the knife hinge leaf is inserted into the mortise. The depth of the mortise should be equal to the thickness of the knife hinge leaf, in this case 1/8 inch. I'll continue on with these steps and install and adjust the doors so they are both plumb, level and spaced evenly to both each other and the carcase itself.

It looks like we've been hit with an early winter up here, typically there is little snow on the ground before Christmas. I've taken up downhill skiing again after many years and I'm kind of glad to see the snow, planning the first ski trip already.

1 comment:

Mat Nedeljko said...

Norman, I've just discovered your blog and have avidly read all of your posts. I'm thoroughly enjoying your description of the building process of the jewelry armoire.

I've never tried knife hinges, they seem like they need to be executed perfectly in order to work properly. As you say, very little room for error.

That said, I'm looking forward to your next installment, so please keep them coming.